我有一个 PostgreSQL 函数脚本，用于根据作为参数传递给函数的记录数模拟某些表。执行脚本时发生的事情是它必须检查现有记录然后插入，即增量加载，因此花费的时间非常长。我怎样才能提高这个脚本的性能？我把我的脚本放在这里:
CREATE OR REPLACE FUNCTION ccdb.perf_test_new(records bigint)
RETURNS void AS
$BODY$
DECLARE
i bigint;
count bigint;
bill_mnth integer;
j integer;
cin_num bigint;
BEGIN
count := records;
bill_mnth := 201400;
FOR i IN 1..count
LOOP
INSERT INTO ccdb.consumer_index_details_new
(
cin
,pole_lmdt
,meter_lmdt
,dtr_lmdt
,r_apdrp_town_flag
,town
,creation_dt
,created_by
)
SELECT nextval('ccdb.cin_gen')
,now()
,now()
,now()
,1
,'Kottayam'
,now()
,'System';
INSERT INTO ccdb.consumers_new
(
cin
,consumer_num
,first_name
,org_unit_id
,source_system_flag
,cust_area_type
,cons_cat_flag
,legacy_consumer_num
,cust_connection_id
,purpose_id
,tariff_id
,connected_load
,connected_load_uom
,consumer_phase
,supply_voltage
,connection_date
,bill_freq_id
,conn_status
,conn_category_group_id
,conn_cat_subgroup_id
,conn_address
,billing_address_1
,billing_address_dist
,permanent_address
,communication_address
,conn_owner_address
,pricing_type_flag
,conn_owner_customer_id
,ownership_flag
,district_id
,sanction_load
,sanction_load_uom
,advance_amount
,total_arrear
,dc_date
,creation_dt
,created_by
,cdemand_unit
)
SELECT
ci.cin
,(SELECT CASE WHEN MAX(consumer_num) IS NULL THEN 1146341200001 ELSE ((MAX(consumer_num))+1) END FROM ccdb.consumers_new)
,'Perf_Test'||i
,4634
,1
,2
,1
,16876
,(SELECT CASE WHEN MAX(cust_connection_id) IS NULL THEN 1146340000001 ELSE ((MAX(cust_connection_id))+1) END FROM ccdb.consumers_new)
,15
,1
,800
,'W'
,1
,300
,now()
,2
,1
,1
,1001
,'SAPEER MANZIL,,KARAPUZHA P O,,KOTTAYAM,'
,'SAPEER MANZIL,,KARAPUZHA P O,,KOTTAYAM,'
,'KOTTAYAM'
,'SAPEER MANZIL,,KARAPUZHA P O,,KOTTAYAM,'
,'SAPEER MANZIL,,KARAPUZHA P O,,KOTTAYAM,'
,'SAPEER MANZIL,,KARAPUZHA P O,,KOTTAYAM,'
,1
,(SELECT CASE WHEN MAX(conn_owner_customer_id) IS NULL THEN 1146340001 ELSE ((MAX(conn_owner_customer_id))+1) END FROM ccdb.consumers_new)
,1
,5
,600
,'W'
,45
,3
,now()
,now()
,'System'
,'KVA'
FROM ccdb.consumer_index_details_new ci
WHERE cin > (SELECT MAX(cin) FROM ccdb.consumers_new);
SELECT MAX(cin) INTO cin_num FROM ccdb.consumers_new;
FOR j IN 1..5
LOOP
INSERT INTO ccdb.bills_new
(
bill_id
,source_system_id
,mbc_bill_id
,mbc_bill_no
,cin
,cust_connection_id
,consumer_number
,cust_type_flag
,bill_type_group_code
,bill_type_code
,bill_month
,total_consumption
,bill_date
,due_date
,dc_date
,org_unit_id
,parent_bill_id
,category_flag
,status_flag
,conn_cat_subgroup_id
,dispute_flag
,inst_flag
,approved_date
,bill_amt
,paid_amt
,creation_dt
,created_by
)
SELECT
nextval('ccdb.bills_seq')
,1
,(SELECT CASE WHEN MAX(mbc_bill_id) IS NULL THEN 1000000001 ELSE (MAX(mbc_bill_id))+1 END FROM ccdb.bills_new)
,(SELECT CASE WHEN MAX(mbc_bill_no) IS NULL THEN 4634000000001 ELSE (MAX(mbc_bill_no))+1 END FROM ccdb.bills_new)
,c.cin
,c.cust_connection_id
,c.consumer_num
,1
,'EB'
,'RgCC'
,bill_mnth+j
,400
,now()
,now()
,now()
,4634
,currval('ccdb.bills_seq')
,1
,3
,c.conn_cat_subgroup_id
,0
,0
,now()
,1000
,700
,now()
,'System'
FROM ccdb.consumers_new c
WHERE c.cin = cin_num;
INSERT INTO ccdb.bill_head_details_new
(
bill_id
,charge_head_code
,amount_billed
,amount_paid
,ccdb_update_time
,creation_dt
,created_by
,tariff_id
,demand_date
)
SELECT
bill_id
,'EB'
,1000
,700
,now()
,now()
,'System'
,1
,now()
FROM ccdb.bills_new
WHERE bill_id > (SELECT MAX(bill_id) FROM ccdb.bill_head_details_new);
END LOOP;
INSERT INTO ccdb.payments_new
(
payment_id
,receipt_id
,source_system_flag
,cin
,consumer_nbr
,cust_connection_id
,cust_type_flg
,receipt_type_id
,mop_code
,coll_effect_date
,coll_entry_date
,receipt_num
,receipt_amt
,receipt_loc_flg
,receipt_date
,cancel_flag
,acc_type_id
,cust_section_code
,coll_section_code
,remarks
,pm_paydate
,pm_amount
,creation_dt
,created_by
)
SELECT
nextval('ccdb.payments_seq')
,'REC/35747/2013'
,1
,c.cin
,c.consumer_num
,c.cust_connection_id
,1
,27
,2
,now()
,now()
,(SELECT CASE WHEN MAX(CAST(receipt_num AS bigint)) IS NULL THEN 102820110000001 ELSE (MAX(CAST(receipt_num AS bigint)))+1 END FROM ccdb.payments_new)
,700
,1
,now()
,0
,1
,4634
,4634
,'ONCOUNTER'
,now()
,700
,now()
,'System'
FROM ccdb.consumers_new c
JOIN ccdb.bills_new b ON c.consumer_num = b.consumer_number
AND c.cin > (SELECT MAX(cin) FROM ccdb.payments_new);
INSERT INTO ccdb.payment_head_dtls_new
(
payment_id
,mbc_receipt_id
,charge_head_code
,amount
,tariff_id
,creation_dt
,created_by
)
SELECT
payment_id
,receipt_id
,'EB'
,700
,1
,now()
,'System'
FROM ccdb.payments_new
WHERE payment_id > (SELECT MAX(payment_id) FROM ccdb.payment_head_dtls_new);
END LOOP;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
ALTER FUNCTION ccdb.perf_test_new(bigint)
OWNER TO postgres;
当我在表中没有记录的情况下执行大约 10,000 条记录的函数时，它会在大约 7 分钟内完成，但是当我尝试在初始插入后为另外 10,000 条记录运行它时，它会持续大约 5-6几个小时，但它仍然没有完成，我不得不结束这份工作。我对 psql 比较陌生，有人可以建议我如何提高此类脚本的性能吗？
谢谢。
最佳答案
您可以为循环做的是使用显式游标并尝试提高性能。
关于PostgreSQL 提高 PL/pgSQL 函数的性能，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22601549/